Hot top



Aug. 4, 1936. E. J. TURNER ET AL 2,049,98Q

HOT TOP Filed Feb. 6, 1934 alHo,

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INVENTORS n wit M mwm A. TM

" 6 swan/0mm Patented Aug. 4, 1936 UNITED STATES PATENT oFFicE HOT TOPDelaware Application February 6, 1934, Serial No. 709,956

1 Claim.

The present invention relates to an improve? ment in hot tops; andmore'particularly to an improvement in the hot top shown in the Patentto Turner 1,593,518.

8 The hot top shown .therein has proved advantageous in operation inthat the same functions more efliciently in affording a reservoirof-metal which flows into the body of the ingot during solidification ofthe mass of metal therein. The

10 portion of the metal confined within the hot top which is availableto thus flow into the body of the solidifying ingot depends to a largeextent upon the insulating properties of the hot top. The hot topdisclosed in said patent operates so 15 efliciently to provide areservoir of molten metal that the required volume within the hot topmay be decreased an appreciable amount, thus reducing the amount ofmetal which must be discarded.

We propose to improve the insulating proper- 20 ties of the hot top byheating up the refractory material of which the hot top is formed beforethe ingot is completely poured. During the pour- I ing operation, moltenmetal enters the ingot mold at a temperature upwards of 2900. Of course,

5 the metal entering the mold displaces air which must flow upwardly outof the mold; and during its upward passage this air attains a hightemperature. We propose to extend the openings in the side walls of thehot top so as to permit flow of hot 30 gases vertically through theseside walls.. The thickness of refractory material surrounding thesevertical passageways is small enough so that by the time the ingot ispoured and the hot top is, filled with molten metal, the refractorymate- 35 rial has been preheated by the upwardly rising air to a hightemperature. At this time the molten metal reaching the lower ends ofthe passageways freezes therein and seals the same so that the sidewalls which are now at a high temperature prevent the dissipation oftheheat of the reservoir of molten metal within the hot top, theinsulating efiect being aided by the air spaces formed in the sidewalls.

The conservation'of the heat in this molten metal in the hot top isaided by using a top wall or lid shading or sheltering the marginalportions of the top of the mass of metal confined within the hot top.The extent of such protection is obviously determined by the sizeofpouring. opening which must be provided in the lid.

In the accompanying drawing which illustrates our invention,

Fig. 1 is a plan view of a hot top with lid, the side walls being formedwith vertical passages therethrough;

Fig. 2 is a side view partially broken away on the line II--II of Fig. 1of the hot top shown in that figure, the top of the ingot mold beingshown in chain lines;

Fig. 3 is a view similar to Fig. 1 showing a hot 5 top without lid;

Fig. 4 is a view similar to Fig. 2 showing the form of hot top of Fig. 3and partially broken away on the line IV-IV of Fig. 3.

The composition of material determined upon for use in manufacturing thehot top may be formed into suitable shape by molding, extrusion, or thelike. The hot top is formed with side walls 6 having vertical passagestherethrough. This is readily accomplished by providing compound wallscomprising an inner shell 8 and an outer shell 9 connected by relativelynarrow ribs or webs ill. The above mentioned vertical passages l2 extendthrough the side walls 6 from bottom to top, and are adapted to permitflow of hot gases upwardly through the walls of the hot top as themolten metal is poured into the ingot mold iii.

In the form of hot top shown in Figs. 1 and 2 a marginal top wall or lidi5 surmounts the side Walls 6, the lid l5 terminating short of the outer5 shell 9 so as to afford free passage for gases rising through thepassages l2. .In the embodiment shown in the drawing the borders of thelid are restricted so as not to overlie the passages I 2. The lid shouldbe so arranged that its edge portions are in spaced relation to theouter side' wall or shell 9; and accordingly these edge portions of thelid should be upturned if they extend outwardly in an appreciable amountover the passages l2. The lid I5 is provided with a pouring opening l6such as is required to admit the stream of molten metal. In the form ofhot tops shown in Figs. 3 and 4, the lid 15 is omitted.

The hot top may be positioned in the desired relation to the top of theingot in any suitable 40 fashion. In the form of vhot top shown in Fig.2 we have provided the same with cut-outs l8; and the hot top is blockedup at the desired level by blocks i9 resting on the top of the ingotmold l3 and having their upper inner edges entered in the cut-outs I8.In the form of hot topshown in Figs. 3 and 4, ribs 20 integral with thesine wall of the hot top are formed in the course of manufacture of thehot top; and these ribsengage blocks 2i of suitable thickness which aresupported by the top of the ingot mold l3. It will thus be understoodthat the means for supporting the hot top may comprise lugs, ribs,cut-outs or any other convenient type of support.

The advantages of the present invention arise 5 in part from the highertemperature at which it is possible to maintain the mass of metal in thehot top during the time that solidification is taking place within theingot mold proper.

While we have illustrated and described certain preferred forms of ourinvention it will be understood that the contour, composition and otherincidents to the formation of the hot top may be modified; and thataccordingly the invention may' be otherwise embodied and practicedwithin the scope of the following claim.

We claim:

As an article of manufacture, an ingot mold hot top formed with compoundside walls comprising inner and outer shells of refractory materialconnected by ribs or webs providing air spaces therebetween which spacesare open at both the top and the bottom, and a lid integral with the topof the inner shell, said lid having a central pouring opening andterminating in spaced relation to the outer shell to leave open the topsof said air spaces.

ERNEST! J. TURNER.

WILLIAMA'I'URNER.

